A lot of research has been carried out in medicine and artificial intelligence domain and several fuzzy expert systems have been developed for diagnosing severe disease, such as liver disorders, blood disease, tuberculosis and many more. A very common disease, viral infection is caused due to viruses that use host cells to reproduce and disturb the immune system. In this paper the framework to construct a fuzzy expert system for mobile users is proposed to diagnose viral infections. The fuzzy expert system shall be hosted on the web-server and web-services shall be used as a communication medium between the fuzzy expert system and the handheld devices. Thus the mobile users will be able to achieve quick assistance for their common disease symptoms which a medical practitioner would suggest when they visit the clinic. With the world converging towards handheld devices, assistance in terms of medicine for common diseases on such devices can be very fruitful with respect to time and security.